Abstract: A catalyst system, a polymerization process using that catalyst system and polymers produced therefrom. The catalytic system results from the combination of bridged indenyl metallocenes of general formula I and an organoaluminium or boron perfluorinated co-catalyst, where M is a transition metal of Group 4 of the Periodic Table of the elements, Q is a divalent substituent and X1 and X2 are monovalent anionic ligands. Polyethylene copolymers made with such catalysts can have from narrow to broad to bimodal molecular weight distribution and melt indexes from about 0 to higher than 10 without the need of molecular weight regulators, depending on proper selection of the indenyl substituent, number of substituents (single or both indenes substituted) and the type of stereoisomeric form used: pure (racemic or meso) or mixtures thereof.